Art of refining oils and other liquids



May 8, 1928. 1,669,182

vo. WERNER ART 0F REFINING OILS AND OTHER LIQUIDS Original Filed Nov, l0, 1925 scazr werner* Patented May 8, 1928.

PATENT OFFICE.

OSCAR WERNER, OF SOUTH BEND, INDIANA.v

ABT 0F REEINING OILS AND OTHER LIQUIDS.

Application led November 10, 1925, Serial No. 68,131. Renewed March 28, 1928.

The discovery and invention relate more particularly to a new and useful method of and means for reclaiming used lubricating oils, and for driving off the lighter constituents such as gasoline and distillates that have mixed with the lubricating oils during use in internal combustion motors. It is also applicable to other refining processes.

Objects of the invention are to provide a device wherein the heat required to drive off said lighter constituents is obtained by indirect means, thereby decreasing the fire risk; and to employ high temperatures with pressures that are low and safe. A feature of the invention is that the heat applied to the oil is closely and automatically maintained at any desired temperature, without dangerof local over heating and without excessive carbon formation.

An object is to make provision whereby the operation is continuous and automatic, and no particular skill is required on the part of the operator.

The principle of this discovery and invention is that by theuse of mercury vapors as a medium for heating oil for refining the same, the high temperatures required in oil refining processes may be employed at comparatively low pressures.

Other objects, advantages, and features of invention may appear from the accompanying drawing, the subjoined detailed description and the appended claims.

The discovery and invention is adapted to varied uses with different kinds of oils and other liquids to be distilled and refined. and the following specification is intended only as typical of the various forms, which' the invention may take. l

The discovery and invention may be understood by reference to the accompanying drawing which illustrates apparatus constructed in accordance with this invention.

Figure 1 is a broken front elevation partially in section showing a preferredconstruction of the novel apparatus adapted for use in conducting this novel method. The stack, the fuel supply, the vent and the discharge pipes are broken away in part to contract the view.

Fig. 2 is an enlarged side view of one of the evaporating members and a fragment of the pan of the mercury boiler shown in Fig. 1.

Fig. 3 is a bottom viewof what is shown in Fig. 2.

A denotes a. tank containing oil to be treated; B is a still wherein the lighter and undesirable constituents of the oil are driven off; C is a condenser wherein the products of the ,still are cooled; D is-a mercury boiler which furnishes mercury vapor for operation of the still; E is a pipeline for carrying mercury vapor from the boiler to the still; and F is the return line for returning the condensed mercury from the still to the boiler.

A char em of mercury will be introduced into the oiler D through a filling plug p to a predetermined level, and in normal operation will remain undiminished indefinitely. l

The `tank A may be of any convenient form and is open at the top, and liquid discharges therefrom through pipe 1, regulating valve 2, shut-off cock 3 and pipe 1 at the desired rate on top of the heating member 4 so as to distribute the flow of liquid evenly all around said member.

Heating member 4 is preferably a hollow cylindrical casting fitted with a number of integral circular shelves 5 for the purpose of retarding the flow of the oil, and of creating a larger surface contact therewith. Said heating member is fitted at its bottom with an annular collecting groove 6 which discharges through a passage 7 into pipe line v 8. Hot mercury vapors are admitted from pipe line E into the interior of heating member 4, through passage 9, and coming.

into contact with the comparatively cool inner walls of heating member 4, condense and form metallic mercury which collects in the cone shaped bottom 10 of the heating member, and is returned through passage 11 and pipe-lino F to the mercury boiler D.

Heating member 4 is surrounded by a shell 12 provided with top 14 and bottom 13. Fitted to the top 14 is stack 15 which may lead to the atmosphere or to a condenser of any well known form, not shown, where the more volatile oil fumes going up thestack are condensed to liquid.

16 is the drain pipe leading from the bottom 13 of the heating member shell 12 to the condenser C which is a vessel filled with water and containng a worm 8 connected to the pipe line 8 and terminating in a pipe line 8 and also'containing a worm 1G connected to the drain pipe 16 and terminating in a pipe line 16 for the purpose of cooling the liquids entering through pipe lines 8 and 16.

Worms 8 and 16 are preferably horizontal so that coils are always partially fillerl with liquid, thus making it impossible for any air to enter the inside of shell 12.

The boiler D contains a mercury evapora tor 17, which is preferably a circular casting forming a pan 18 provided at its bottom with a number of hollow evaporating members 18 which will be hereinafter described more fully; and tightly closed at its top by cover 17. The evaporator 17 connects through side outlet 19 with mercury return line F andl its cover 17 connects through top outlet 2O with mercury vapor line E.

A suflicient supply of metallic mercury is carried in the evaporator to normally keep the evaporating members filled with mercury at all times.

Arranged below the evaporator is a burner 21 supplied through line 22, fuel pressure control valve 23 and line 24 with gaseous or liquid fuel. A pilot light 25 which is constantly supplied with fuel through pipe line 25 is burner 21.

The evaporator and the burner are enclosed in a shell 26, 26 and 26 and dome 27, terminating in the stack 28 leading to the outside of the building, not shown.

Mercury vapor line E communicates through branch line 29 with pressure diaphragm 30 and pressure gage 31. Pressure provided in order to light the diaphragm 30 through stirrup 31 and rod 32 operates fuel pressure control valve 23, thereby controlling the flame produced by burner 21 in such a way as to maintain-automatically any desired pressure of the mercury vapor in the system.

Branch line 29 is provided for a portion of its length with cooling fins 33 in order to keep 'down its temperature.

ercury vapor line E also communicates through branchlline 29 with safety valve 34, the discharge line 35 of which terminates in the vessel 36,' which is filled with water for the purpose of condensing and recovering any mercury vapors which may escape through said safety valve.

Branch line 29 isprovided with cooling fins 33.

Evaporating member 18 is preferably a short tubular downward extension of p an 18 and is closed at the bottom and normally filled with a charge m of metallic mercury. A number of fins 40 are provided surround-y ing the lower portions of the evaporating members 18 in order to increase the surface exposed to the hot gases of combustion and to transfer as much heat as possible to, the mercury within. The upper portions of the evaporating members are -devoid of fins so to allow lateral escape of the gases of combustion which flow upwards along and between the fins 40 and strike upon and collect against the bottom of the evaporator pan 18.

The evaporating members 18 are mounted close together and constitute almost the entire bottom of the evaporator 17.

In practice the pilot light 25 is lit and will light the main fla-me of burner 21 when the fuel is turned on; the gases of combustion will travel upwards along the fins of the heating members 18 and striking the evaporator pan, will follow along its bottom and will escape through the annular space 41 between the evaporator 17 and the shell 26 into stack 28, as indicated by arrows.

The mercury in the evaporator will soon commence to'boil and mercury vapors will rise in pipe E, flow through passage 9 into the interior of heating member 4, to which it imparts its heat, and, condenses against the comparatively cool surfaces as described. The condensate as metallic mercury will return through downwardly. sloping pipe line F to the evaporator, thus establishing a closed circuit.

As soon as heating member 4 has reached its working temperature as indicated by the pressure on gauge 31, the operator will open shut-off cock 3, to allow untreated oil from tank A to fiow slowly over the outside of the heating member 4, as described, and in its slow downward passage the oil will be sufficiently heated by contact to drive off its more volatile undesirable constituents such as gasoline, distillates' and water.

The purified oil will collect in annular groove 6 and enter pipe line 8 connected thereto and after having passed through worm 8', will discharge through pipe 8 in a more or less continuous flow into a filter of well known type, not shown, where any remaining solid matter may be removed.

The fumes boiling off of the lighter constituents will rise in the annular space S between the heating member 4 and the shell 12, land will discharge through vent 15, as indicated by arrows, and may discharge into the atmosphere, or may flow to a condenser, not shown, for the purpose of recovering in a. well known manner, the gasoline and kerosene driven off.

The drain 1'6 is provided to remove the heavier distillates, which may recondense against the comparatively cool inside of shell 12, and are discharged through cooling worm 16 and outlet pipe 16 into a suitable receptacle, not shown.

The plpes E and F are heat insulated and the boilerand still are spaced apa-rt such a distance that the fire hazard is minimized, as no open ame is applied to the vessel containing the oil; and therefore breaking or cracking of the heating member in the still or any overflowing of the oil, will be harmless. The still and the mercury boiler can be located a considerable distance apart without interfering with their operation.

By this novel method the high temperatures required to treat the oil is reached with very little pressure, thus imposing very little strain on the apparatus, and eliminating dangers usually connected with heaters under high pressure.

A mercury vapor pressure below atmospheric may be employed in some instances to carry on the refining process.

The boiling point and the condensation temperature of mercury vary in exact proportion to the pressure, and consequently any of the well proven devices for automatically maintaining the pressure of steam through control of the flame, can be applied to automatically, and with minimum attention of the operator, maintain the desired pressure and the temperature corresponding thereto.

By this discovery and invention the temperature may be automatically maintained between close limits so that no scorching and burning of the oil is possible and the heating member of the still will have a uniform temperature throughout, without hot spots.

The close and continuous temperature control obtainable, by the apparatus shown, makes it possible to so adjust the flow of the untreated oil, that, when the oil reaches the collecting groove at the bottom of the heating member, all the lighter constituents will have been driven off, and by maintaining a given setting of the regulator valve for any given quality of oil, the process may be continuous and automatic without requiring further attention on the part 0f the operator.

The temperatures of the mercury vapors and the temperature of the oil to which they are applied are easily regula-ted by regulating the pressure of-the mercury vapors, as similar to steam, a certain boiling temperature and condensing temperature corresponds to cach pressure; and'further, the heat in the apparatus will at no place exceed that temperature, thus avoiding hot spots and the liability ofburning the oil.

In case of accidental breakage the mercury vapors, which would then have access to the oil cannot ignite same as they carry no oxygen.

It will be apparent to those skilled in the art that a large number of variations and combinations may be made in the mechanical structure and design of the mechanism and still utilize the fundamental principles of operation and structure that are herein explained.

i boiler of a series of tubes; or the heat escapmg through the boiler chimney may be utilized in pre-heating air for the burner; or the heating member of the still may be 0f a varied form, such as a coil of tubing over the outside of which the oil trickles in a continuous flow, or a hollow cylinder with smooth outside, or with a continuous shelf running around it in the form of a thread; or the shell of the still may be insulated against heat transmission in order to avoid any condensation on the inside thereof; or the mercury vapor line may enter the heating member at its bottom and may serve for the return to the boiler of the metallic mercury, as usual with steam heating installations; or a portion of the mercury vapor produced may be admitted to a second still, the pressure in which is automatically maintained at a lower level, thus producing a lower temperature, land the condensate of which isreturned to the boiler by a pressure pump; or all of the volatile vapors enterin the vent pipe of the still may e condense in some suitable condenser; or a thermostatic control of the flame may be used instead of a ressure control and so on.

In practlce a working temperature of 600 degrees F. for the mercury vapor delivered to the still may be had at a comparatively low pressure, viz., about five pounds per square inch above atmosphere.

I claim:

1. The combination with a mercury heater comprisin a pan having downwardly extending tu es; a cover for the pan; a dome surrounding the cover and provided wlth a. stack; an oil heater; a' pipe leadin from the cover to the top of the oil heater t rough which mercury vapor is passed; a pipe leading from the bottom of the oil heater throuvh which condensed mercury 1s returned to the pan; a shell open at the bottom forming a continuation of the dome and surrounding the pan; a end of the shell below the pan; a shell surrounding the oil heater; an annular collector at the bottom of and on the exterior of the oil heater; a drain leadingr from said collector; a drain from said shell; and means to deliver oil to the top of the oil heater in a regulated stream.

2. The combination with a mercury heater, comprising a vaporizing an havlngdownwardly extending tubes c osed at their lower ends; a cover for the pan; a dome surrounding the pan and provided with. a stack; an oil heater; a mercury vapor pipe leading from the cover to the top of e oil heater; a mercury from the bottom of the oil heater to the burner at the open return pipe leading lll) drain leading from said collector; a drain leading from Said shell;

means to deliver oil to the top of the oil heater in a regulated stream and means o erated by vapors from l0 the pan to regulate t e heat of the oil burner.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 4th day of November, 1925.

OSCAR WERNER. 

